Doubs (river)

The Doubs (Dubs; Dub (obsolete)) is a 453 km river in far eastern France which strays into western Switzerland. It is a left-bank tributary of the Saône. It rises near Mouthe in the western Jura mountains, at 946 m and its mouth is at Verdun-sur-le-Doubs, a village and commune in Saône-et-Loire at about 175 m above sea level. It is the tenth-longest river in France.

The most populous settlement of the basin lies on its banks, Besançon. Its course includes a small waterfall and a 4 km narrow lake.

Course
From its source in Mouthe it flows northeast: a few kilometers north of the French-Swiss border, then to form the border for less distance, about 40 km. North of the Swiss town of Saint-Ursanne it turns west then southwest. South-east of Montbéliard it adopts a southwest striation or fault of the Jura Mountains, flowing so over greater distance than the flow it has traced before. It then flows into the Saône at Verdun-sur-le-Doubs about 20 km northeast of Chalon-sur-Saône.

The shape of the course resembles the silhouette of a terrier sitting upright, leaning right, with the upper part of a northeastern corner "ear" the only zone in Switzerland, there reaching Saint-Ursanne. In that country it borders or crosses the cantons Jura and Neuchâtel.

Waterfalls and lake
The falls known as the Saut du Doubs is on the French-Swiss border.

Nearby, the river, dammed up by landslide debris, forms the 4 km long, 200 m wide, winding lake, (le) Lac des Brenets. The 27 m-high Doubs Falls are at the lake's end. The falls can be reached on foot or by passenger boat.





The Doubs flows through the following Departments of France, Cantons of Switzerland, and cities:


 * Doubs (F): Pontarlier
 * Neuchâtel (CH)
 * Jura (CH): Saint-Ursanne
 * Doubs (F): Montbéliard, Besançon
 * Jura (F): Dole
 * Saône-et-Loire (F): Verdun-sur-le-Doubs

Tributaries include:
 * Loue
 * Dessoubre
 * Allan

The river forms several lakes:
 * Lac de Saint-Point (elevation 850 m) near Pontarlier
 * Lac des Brenets (elevation 750 m)
 * Lac de Moron (elevation 716 m)
 * Lac de Biaufond (elevation 610 m)



Floods and seasonal variation
The rate of flow of the Doubs is very seasonally variable. The flooding or well-watered season can stretch from September to May, caused by heavy rains or by quick melting of snow from the Jura mountains. At its mouth, the discharge rate can vary from as low as 20 m3/s to over 1000 m3/s during floods.

In Besançon, the largest floods have been in 1852 (8.5 m), in 1896 (7.96 m) and in 1910.

Hydroelectricity


As a mountain river with substantial discharge, the Doubs has been used for electricity generation. Among several hydroelectric stations, the most important are the Dam of Châtelot, 74 m tall, and the Dam of Refrain, 66.5 m tall.

In popular culture
The river is mentioned sixteen times in Stendhal's novel The Red and the Black (Le rouge et le noir).